From the References menu, choose New Reference

1.Enter all of the bibliographic information that the references have in common (such as the year, book title, publisher, and city for different sections from one book).
2.Close the reference when you are finished. It remains selected in the Library window.
3.Choose Ctrl-C from the Edit menu.
4.Use the Ctrl-V command to paste the reference several times, to create as many partially-filled references as you need. You should paste directly to the Library window—do not open a new reference.